|Code|County|Former Province|Area (km2)|Population Census 2009|Capital|
|---|---|---|---|---|---|
|1|Mombasa|Coast|212.5|939,370|Mombasa (City)|
|2|Kwale|Coast|8,270.3|649,931|Kwale|
|3|Kilifi|Coast|12,245.9|1,109,735|Kilifi|
|4|Tana River|Coast|35,375.8|240,075|Hola|
|5|Lamu|Coast|6,497.7|101,539|Lamu|
|6|Taita-Taveta|Coast|17,083.9|284,657|Voi|
||Totals||79,686.1|3,325,307|-|

Question: how many counties have a population greater than 500,000?
Answer: 3